If your solution is just water and CaCl2, you can distil the water off and separate the two that way. If you need to specifically remove Ca from your solution, you can add citrate, which will combine to the insoluble calcium citrate. From there you can simply filter it out.

I. You may consider to alkalinise the solution, possibly by adding sodium (or potassium) hydroxide, what would quantitatively precipitate the alkaline earth hydroxide. By heating the mother solution it is possible to decrease the solubility of Ca(OH)2, which would further precipitate. The precipitate could then be separated by vacuum filtering or centrifugation, and redissolved, with diluted hydrochloric acid, as CaCl2. The remaining mother brine may, in principle, be recycled, to some extent.

II. You may consider to carbonate the solution with pressurized CO2 and adjust the pH, to precipitate calcium carbonate, from which CaCl2 can be regenerated (cf. I).

III. You may consider to precipitate calcium as sulfate, after acidifying the solution with H2SO4, possibly adding some soluble sulfate salt, (e.g. sodium sulfate), and neutralizing the pH to that of pure CaSO4 solution or some suitable pH judged to favour CaSO4 precipitation.

IV. You may want to consider desalination by reverse osmosis.

V. You could consider desalination/decalcification by ion exchange using chelating ion exchange resins.

About predicting the pH of CaCl2 aq. solutions ― cf. my posts at: https://www.researchgate.net/post/How-to-increase-pH-for-a-solution-without-making-a-chemical-reaction-with-CaCl2

Mr. Carlos Araújo Queiroz; please i don't understand the last answer (V).

Referring to §V. from my 1st post, above:

Aminophosphonic cationic chelating resins can be used in the sodium form to selectively adsorb divalent Ca2+ cations, over Na+ cations, from alkalized CaCl2 based solution/brine ― possibly after Ca(OH)2/Na2CO3/NaOH addition. This kind of resin has been used for brine softening in the chlor-alkali industry. Regeneration can be achieved with mineral acid followed by conversion to sodium form using NaOH (aq).

Cf. US Patents 9,677,181 B2 (Jun. 13, 2017) and US 10, 066,305 B2 (Sep . 4 , 2018); European Patents EP 2 855 735 B1 (07.03.2018), EP 3 363 930 A1 (22.08.2018), and EP 3 060 522 B1 (12.06.2019).

About predicting the pH of mixed CaCl2/Ca(OH)2 aq. solutions ― cf. my posts at:

https://www.researchgate.net/post/How-to-increase-pH-for-a-solution-without-making-a-chemical-reaction-with-CaCl2

Dear Zeineb Hamden thank you for your interesting technical question. I think that Carlos Araújo Queiroz already provided a rather comprehensive answer. Once you have precipitated CaCO3, you can easily regenerate calcium chloride by dissolving the carbonate in hydrochloric acid (CO2 will be liberated) and evaporating the solution to dryness.

This brings me to another point: Depending on the amount of CaCl2 solution you have, why don't you just evaporate the solution do dryness? You could use a rotary evaporator and evaporate all the water under vacuum. This should leave the pure CaCl2 behind (unless you have tons of solution...).

Dear professor Frank T. Edelmann ; Thank you very much for your answer, but yes I have tons of CaCl2-Water mixtures solutions, so in this case the evaporation is very expensive. So, please professor, what is the best solution or method for separation or concentration CaCl2

Given that, the concentration of CaCl2 is 7%.

Dear Zeineb Hamden many thanks for your further explanation. If your goal is the separation of the calcium form your solution, you might perhaps add the calculated amount of soda (Na2CO3 x 10 H2O) in order to precipitate the calcium as calcium carbonate (CaCO3). This could then be isolated by filtration, redissolved in a smaller amount of hydrochloric acid and then crystallized as calcium chloride hydrate.

In this context please also have a look at the following potentially useful article which might help you in your analysis:

Calcium Chloride Recovery in Soda Ash Production by Solvay's Process

https://www.grin.com/document/207964

Dear Frank T. Edelmann thank you very much for your specific help.

Ryan Wheeler by meaning of citrate can you please tell me what specifically salt is used? Also, my mixture consists of HCl, water and CaCl2. I want to remove CaCl2.